Speaker
Description
The negatively charged Tin-Vacancy (SnV$^-$) color center in diamond is a promising candidate for solid-state quantum network nodes due to its long spin coherence times and fourier limited optical transitions.
Diamond, as a host material, has a large refractive index of $n=2.4$ which limits the amount of light that can escape past its boundary surface caused by total internal reflection. This restricts the collection efficiency of a single SnV$^-$ color center.
Several approaches have been proposed to increase the detected photon rate, either by enhancing spontaneous emission through the Purcell effect or improving photon outcoupling and collection efficiency.
This work employs a hemispherical solid immersion lens (SIL) made out of diamond with a diameter of 1 mm. Such a geometry remedies the issue of total internal reflection and therefore promises a higher outcoupling rate.
We observe a fivefold increase compared to bulk-like countrates measured on the flat surface. This enhancement in photon collection therefore contributes to the development of efficient quantum network nodes.
